Patent · US Expired

Lock-up clutch fuzzy logic control system of vehicle automatic transmission

US5267158A · kind A · utility

24Cited by
11References
16Claims
0Family size

Assignee

Inventors

Key dates

Filing dateSep 4, 1992
Grant dateNov 30, 1993
Priority date
Expiry dateSep 4, 2012

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S706/90
  • WIPO fieldMechanical elements
  • WIPO sectorMechanical engineering

Abstract

A system for controlling a lock-up clutch of a torque converter in which a target speed ratio of the torque converter of an automatic transmission of a vehicle which mechanically couples a pump impeller connected to an engine output shaft with a turbine runner connected to a transmission input shaft, is determined by carrying out a fuzzy reasoning based on fuzzy production rules using a degree of throttle opening, a grade resistance and a current speed ratio as parameters. Then a second fuzzy reasoning is carried out based on second fuzzy production rules using a deviation between the target speed ratio and the current speed ratio and the change of the deviation as parameters to determine a control value such that the lock-up clutch is controlled between a position at which the clutch is fully engaged and a position at which the clutch is fully not engaged including an intermediate position at which the clutch is partially engaged. With this system, the lock-up control can cope with various vehicle operating conditions so that the vehicle drivability and fuel consumption is improved while suppressing engine noise. This system further enables control that is better matched to the in…

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.